class_docstr: Gym Dictionary with arbitrary keys updatable after instantiation
  
  Example:
     space = FlexDict({})
     space['key'] = spaces.Box(4,)
  See also: documentation for gym.spaces.Dict
code: def sample(self):
      return {k: space.sample() for k, space in self.spaces.items()}
  
file_path: ray/python/ray/rllib/utils/spaces/flexdict.py
imports: import gymnasium
  from ray.rllib.utils.annotations import PublicAPI
label_desc: Use image node_id 3 for calling the FlexDict obj's underlying member method code with example usage: obj.sample() and returns: unknown